Jamil Hamad: Without elections or reliable polls it's hard to say for certain, but they're believed to represent at least 30 percent of the Palestinian population. Some say its support may be as high as 45 percent. But if you reverse the question and ask how many Palestinians would support suppressing Hamas, the answer would be 15 to 20 percent.

Hamas keeps its military wing secret, and separate from its other activities. It is believed to number about 500 people, but it is recruiting all the time. But these are recruited as suicide bombers. They are not a militia like Fatah that goes onto the streets with rifles. It's secret. The public face of Hamas is its medical, welfare and educational services it provides for needy Palestinians. Hamas builds its public support running a network of social welfare activities, helping poor families and the families of "martyrs"  young Palestinians killed in action against Israelis. It's doubtful whether President Bush's action will have much effect on Hamas activity. Most of its support comes from Saudi non-governmental charities, although they are also close to the Saudi government, and from similar charities in all the Gulf States. Hamas activities get a lot of sympathy in the Arab world  both its military and welfare activities. Although government officials will say they are against violence and terror, they say so for American ears. Deep in their hearts, they are happy with what Hamas is doing.

If Hamas is directly challenging Arafat's authority, why has Arafat been reluctant to act against them?

The Palestinian Authority cannot act against Hamas because they are afraid of Hamas. Today, for example, Hamas stopped Palestinian Security forces in Gaza from arresting one of the bodyguards of Sheikh Ahmed Yassin, the head of Hamas. And similar things happened in the West Bank, where Arafat's police were prevented from arresting people. Hamas is a power on the ground, and I think it's an illusion to think that arrests would put an end to Hamas. Hamas is not just a military threat, it's a major political power in Palestinian society.